function objGroup (obj1, obj2) {
  obj1.next = obj2
  obj2.prev = obj1
  return {
    o1: obj1,
    o2: obj2
  }
}

let obj = objGroup({name: 'obj1'}, {name: 'obj2'})
console.log(obj)
/*
{
  o1: <ref *1> {
    name: 'obj1',
    next: { name: 'obj2', prev: [Circular *1] }
  },
  o2: <ref *2> {
    name: 'obj2',
    prev: <ref *1> { name: 'obj1', next: [Circular *2] }
  }
}
*/